What is firefox-patch.js?

I assume you're seeing some kind of "Urgent Firefox Update" pop-up...

If so: That's not from Firefox. That's a fake.

See:

https://support.mozilla.org/en-US/questions/1129758

I found a fake Firefox update

I suggest to run some scans with the tools mentioned in https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware

I'd start with free AdwCleaner (http://www.bleepingcomputer.com/download/adwcleaner/) and free Malwarebytes-Anti-Malware (https://www.malwarebytes.org/free/) (uncheck Enable Free Trial during setup)

I'd also suggest to use some adblocker. I, personally, use uBlock Origin

Here are some other threads on same topic:

http://forums.mozillazine.org/viewtopic.php?f=38&t=3014225

https://support.mozilla.org/en-US/questions/1126567

http://answers.microsoft.com/en-us/protect/forum/protect_other-protect_updating/urgent-update-for-firefox/a265ad95-0f44-4053-9b90-9f125a2d43ce